Tuesday, 30 July 2013

Within the next week, the astronomical mid-point of the season of Summer, in the Northern Hemisphere, will be observed. This point in time is known by the term, Cross-Quarter Day (XQ). Having no formal astronomical definition, "cross-quarter" here is defined as the moment in time precisely half-way between an adjacent equinox and solstice or adjacent solstice and equinox..In this case, the moment in time is precisely half-way between the Summer Solstice (observed on June 21) and the Autumnal Equinox (which will be observed on September 22). Although the traditional cross-quarter day of Lammas (Anglo-Saxon) or Lughnasadh (Irish/Scottish) is observed each year on August 1, the actual cross-quarter day for the year 2013 occurs August 6 at 8:54 p.m. EDT (August 7, 0:54 Coordinated Universal Time).Lammas / Lughnasadh Day is the least known, to the general public, of the four cross-quarter days each year. The other three, traditional, cross-quarter days have long been part of the popular culture: Groundhog Day (February 2), May Day (May 1), and Halloween Day (October 31). Likewise, due to the evolution of our calendar from ancient times, the actual cross-quarter day for each of these holidays also occurs a few days after the traditional date.

Lammas / Lughnasadh Day, in ancient times,was a festival day which marked the start of the harvest season, particularly the wheat harvest. On Lammas Day, it was customary to bring a loaf of bread, from the new crop, to church to be blessed.

Lughnasadh Day, in Irish mythology, is a festival said to have begun by the God Lugh as a funeral feast for his foster-mother, Tailtiu, a goddess said to have died of exhaustion from clearing the plains of Ireland for agriculture.

At about the same time as the mid-point of Summer is the Heliacal Rising of the Star Sirius on August 7. This is the first day, normally, that Sirius can briefly be seen on the eastern horizon just prior to sunrise (seven degrees altitude ahead of the Sun).

As Sirius is the brightest star in the nighttime sky, the ancient astronomers/astrologers believed that the rising of Sirius in the daytime sky added to the heat from the Sun, to make Summer even hotter: The Dog Days of Summer (being in the Constellation Canis Major, Sirius is nicknamed The Dog Star). Although Sirius is much hotter than our Sun, it is much too distant to provide any appreciable heat to our planet.

Special Thanks: Eric G. Canali, former Floor Manager of Pittsburgh's original Buhl Planetarium and Institute of Popular Science and Founder of the South Hills Backyard Astronomers amateur astronomy club.

Source: Glenn A. Walsh, Reporting for SpaceWatchtower, a project of Friends of the Zeiss.

Saturday, 27 July 2013

In astronomy, there's nothing quite like a bright meteor streaking across the glittering canopy of a moonless night sky. The unexpected flash of light adds a dash of magic to an ordinary walk under the stars.

New research by NASA has just identified the most magical nights of all.

"We have found that one meteor shower produces more fireballs than any other," explains Bill Cooke of NASA's Meteoroid Environment Office. "It's the Perseid meteor shower, which peaks on August 12th and 13th."

A new ScienceCast video previews the 2013 Perseid meteor shower. Play it

Using a network of meteor cameras distributed across the southern USA, Cooke's team has been tracking fireball activity since 2008, and they have built up a database of hundreds of events to analyze. The data point to the Perseids as the 'fireball champion' of annual meteor showers.

A fireball is a very bright meteor, at least as bright as the planets Jupiter or Venus. They can be seen on any given night as random meteoroids strike Earth's upper atmosphere. One fireball every few hours is not unusual. Fireballs become more numerous, however, when Earth is passing through the debris stream of a comet. That’s what will happen this August.

The moment when a telescope first opens its doors represents the culmination of years of work and planning -- while simultaneously laying the groundwork for a wealth of research and answers yet to come. It is a moment of excitement and perhaps even a little uncertainty. On July 17, 2013, the international team of scientists and engineers who supported and built NASA's Interface Region Imaging Spectrograph, or IRIS, all lived through that moment. As the spacecraft orbited around Earth, the door of the telescope opened to view the mysterious lowest layers of the sun's atmosphere and the results thus far are nothing short of amazing. The data is crisp and clear, showing unprecedented detail of this little-observed region.

Tuesday, 23 July 2013

A new ScienceCast video ponders the mystery of the missing waves on Titan. Play it

One of the most shocking discoveries of the past 10 years is how much the landscape of Saturn's moon Titan resembles Earth. Like our own blue planet, the surface of Titan is dotted with lakes and seas; it has river channels, islands, mud, rain clouds and maybe even rainbows.

The "water" on Titan is not, however, H2O. With a surface temperature dipping 290 degrees F below zero, Titan is far too cold for liquid water. Instead, researchers believe the fluid that sculpts Titan is an unknown mixture of methane, ethane, and other hard-to-freeze hydrocarbons.

Yet something has been bothering Alex Hayes, a planetary scientist on the Cassini radar team at Cornell University.

Saturday, 20 July 2013

Forty-four years ago, man first landed and walked on another planetary body, the Earth's Moon. On Sunday Afternoon, 1969 July 20, at precisely 4:17:40 p.m. Eastern Daylight Saving Time (20:17:40 Coordinated Universal Time) the Lunar Excursion Module (LEM) named Eagle, with astronauts Neil Armstrong and Buzz Aldrin aboard, landed in the Moon's Sea of Tranquility, at a site from then on called Tranquility Base.

Neil Armstrong became the first human to set foot on the Moon that evening at precisely 10:56:20 p.m. Eastern Daylight Saving Time. Originally, the first steps on the Moon had been planned for the early morning hours of Monday/Moonday. However, the earlier time allowed millions of Americans to view the event, on live television, at the tail-end of Sunday evening's television prime-time viewing period. By the time scale most scientists use, Coordinated Universal Time (UTC), these first steps did occur on Monday/Moonday, 1969 July 21 at precisely 2:56:20.

Should Moon Day, July 20, be designated an official national holiday ?

James J. Mullaney thinks so. Mr. Mullaney, former Curator of Exhibits and Astronomy at Pittsburgh's original Buhl Planetarium and Institute of Popular Science and Staff Astronomer at the Allegheny Observatory, says: "If there's a Columbus Day on the calendar, there certainly should be a Moon Day!"

Mr. Mullaney has been campaigning for July 20 to be officially designated as the Moon Day national holiday for several years. J. Kelly Beatty, Senior Contributing Editor of Sky and Telescope Magazine, supports this campaign, as does Steven L.J. Russo, Director of the East Kentucky Science Center and Planetarium.

In 2003, the International Space Station Fan Club started a petition to designate July 20 as National Space Day. And, on 1999 July 20, the nation of Morocco, at a United Nations conference, proposed that July 20 be designated as International Space Day.

The last day to be designated as a federal holiday was Martin Luther King, Jr. Day, which is celebrated as one of the nation's Monday holidays near the civil rights activist's January 15 birthday (celebrated on the third Monday in January). It took many years to build-up support for such a federal holiday, with the first designation attempt in Congress not coming until 1979, eleven years after Dr. King was assassinated. Due to some political opposition, the holiday designation did not occur until 1983 November 2, when President Ronald Reagan signed the designation bill into law.

The first Martin Luther King, Jr. Day was celebrated 1986 January 20. This celebration occurred eight days before a major tragedy in space history: the explosion of the Space Shuttle Challenger, shortly after launching from Cape Canaveral with the first teacher-in-space, Christa McAuliffe, aboard.

Thus far, support for a Moon Day national holiday seems to be limited to outer space enthusiasts. As Mr. Mullaney notes, if the discovery of the "New World" in 1492 is important enough for a federal holiday, it would reason that man's first step on another world would certainly justify such a designation. So, such a designation, or similar commemoration, will probably occur some day. But, politics being what it is, it would be very difficult to predict when such a day may arrive.

Thursday, 18 July 2013

Hubble's composite picture of blue-hued Neptune, its rings and five of its 14 known moons (Image: NASA/ESA/M. Showalter/SETI Institute)

House lawmakers debated NASA's 2014 budget today (July 18) during a meeting that saw stark partisan divisions over proposed funding cuts for the agency's science and space exploration programs.A NASA authorization bill drafted by the Republican majority of the House Committee on Science, Space and Technology proposes to slash NASA's funding to $16.6 billion for 2014 — $300 million less than it received in 2013, and $1.1 billion less than President Obama requested for NASA in 2014. The bill would roll back NASA's funding to a level $1.2 billion less than its 2012 - See more at: http://www.space.com/22023-nasa-authorization-bill-debate.html#sthash.RAxZC4Ki.dpuf

House lawmakers debated NASA's 2014 budget today (July 18) during a meeting that saw stark partisan divisions over proposed funding cuts for the agency's science and space exploration programs.A NASA authorization bill drafted by the Republican majority of the House Committee on Science, Space and Technology proposes to slash NASA's funding to $16.6 billion for 2014 — $300 million less than it received in 2013, and $1.1 billion less than President Obama requested for NASA in 2014. The bill would roll back NASA's funding to a level $1.2 billion less than its 2012 - See more at: http://www.space.com/22023-nasa-authorization-bill-debate.html#sthash.RAxZC4Ki.dpuf

House lawmakers debated NASA's 2014 budget today (July 18) during a meeting that saw stark partisan divisions over proposed funding cuts for the agency's science and space exploration programs.A NASA authorization bill drafted by the Republican majority of the House Committee on Science, Space and Technology proposes to slash NASA's funding to $16.6 billion for 2014 — $300 million less than it received in 2013, and $1.1 billion less than President Obama requested for NASA in 2014. The bill would roll back NASA's funding to a level $1.2 billion less than its 2012 - See more at: http://www.space.com/22023-nasa-authorization-bill-debate.html#sthash.RAxZC4Ki.dpuf

House lawmakers debated NASA's 2014 budget today (July 18) during a meeting that saw stark partisan divisions over proposed funding cuts for the agency's science and space exploration programs.A NASA authorization bill drafted by the Republican majority of the House Committee on Science, Space and Technology proposes to slash NASA's funding to $16.6 billion for 2014 — $300 million less than it received in 2013, and $1.1 billion less than President Obama requested for NASA in 2014. The bill would roll back NASA's funding to a level $1.2 billion less than its 2012 - See more at: http://www.space.com/22023-nasa-authorization-bill-debate.html#sthash.RAxZC4Ki.dpuf

Neptune has a new moon, and its existence is an enigma. The object, known for now as S/2004 N1, is the first Neptunian moon to be found in a decade. Its diminutive size raises questions as to how it survived the chaos thought to have created the giant planet's other moons.

The faint moon was discovered in archived images from the Hubble Space Telescope. Mark Showalter of the SETI Institute in Mountain View, California, was poring over pictures of Neptune taken in 2009 to study segments of its rings.

The rings around our outermost planet are too faint to see without taking very long-exposure pictures. However, the rings orbit so fast that taking one long shot would smear them across the frame. Showalter and colleagues gathered multiple shorter-exposure images and developed a technique to digitally rewind the orbits to the same point in time. Then they could stack several images on top of each other to reveal details of the rings.

"I got nice pictures of the arcs, which was my main purpose, but I also got this little extra dot that I was not expecting to see," says Showalter.

Stacking eight to 10 images together allowed the moon to show up plain as day, he says. When he went back and repeated the process using Hubble pictures taken in 2004, the moon was still there and moving as expected.

The tiny addition to Neptune's family is an added shock because it seems too small to have survived the formation of the other moons, according to accepted theories.

If you need cardiac surgery in the future, aortic dissection in particular, reach for the moon. Or at least try to schedule your surgery around its cycle. According to a study at Rhode Island Hospital, acute aortic dissection (AAD) repair performed in the waning full moon appears to reduce the odds of death, and a full moon was associated with shorter length of stay (LOS).

The study is published online in advance of print in the journal Interactive Cardiovascular and Thoracic Surgery.

The purpose of the study was to assess the effect of natural time variations of both the season and the lunar cycle phase on hospital survival and length of stay (number of days a patient is in the hospital) following acute aortic dissection repair.

"While there has been previous research of seasonal impacts on cardiovascular disease, there has not been any data about the effect of the lunar cycles on cardiac cases, until now," said senior author Frank Sellke, M.D., chief of cardiothoracic surgery and co-director of the Cardiovascular Institute at Rhode Island, The Miriam and Newport hospitals. "We focused the study on patients having aortic dissection and found that the odds of dying following this procedure were greatly reduced during the waning full moon, and that length of stay was also reduced during the full moon."

Saturday, 13 July 2013

This artist's concept shows how the Optical Payload for Lasercomm Science (OPALS) laser will beam data to Earth from the International Space Station. (Credit: NASA)

NASA will use the International Space Station to test a new communications technology that could dramatically improve spacecraft communications, enhance commercial missions and strengthen transmission of scientific data.

The Optical Payload for Lasercomm Science (OPALS), an optical technology demonstration experiment, could improve NASA's data rates for communications with future spacecraft by a factor of 10 to 100. OPALS has arrived at NASA's Kennedy Space Center in Florida from the agency's Jet Propulsion Laboratory in Pasadena, Calif. It is scheduled to launch to the space station later this year aboard a SpaceX Dragon commercial resupply capsule on the company's Falcon 9 rocket.

"OPALS represents a tangible stepping stone for laser communications, and the International Space Station is a great platform for an experiment like this," said Michael Kokorowski, OPALS project manager at JPL. "Future operational laser communication systems will have the ability to transmit more data from spacecraft down to the ground than they currently do, mitigating a significant bottleneck for scientific investigations and commercial ventures."

Thursday, 11 July 2013

Like a comet, the solar system has a tail. NASA's Interstellar Boundary Explorer (IBEX) has for the first time mapped out the structure of this tail, which is shaped like a four-leaf clover.

Scientists describe the tail, called the heliotail, based on the first three years of IBEX imagery in a paper published in the July 10 edition of the Astrophysical Journal.

A new video from NASA explores the solar system's comet-like tail. Play it

While telescopes have spotted such tails around other stars, it has been difficult to see whether our star produced one. The particles found in the tail -- and throughout the entire heliosphere, the region of space influenced by our sun -- do not shine, so they cannot be seen with conventional instruments.

"By examining the neutral atoms, IBEX has made the first observations of the heliotail," said David McComas, IBEX principal investigator at Southwest Research Institute in San Antonio, Texas, and the paper's lead author. "Many models have suggested the heliotail might look like this or like that, but we have had no observations. We always drew pictures where the tail of the solar system just trailed off the page, since we couldn't even speculate about what it really looked like."

Tuesday, 9 July 2013

Antimatter has been detected in solar flares via microwave and magnetic-field data, according to a presentation by the New Jersey Institute of Technology research professor of physics Gregory Fleishman and two co-researchers at the 44th meeting of the American Astronomical Society’s Solar Physics Division. This research sheds light on the puzzling strong asymmetry between matter and antimatter by gathering data on a very large scale using the Sun as a laboratory.

While antiparticles can be created and then detected with costly and complex particle-accelerator experiments, such particles are otherwise very difficult to study. However, Fleishman and the two co-researchers have reported the first remote detection of relativistic antiparticles — positrons — produced in nuclear interactions of accelerated ions in solar flares through the analysis of readily available microwave and magnetic-field data obtained from solar-dedicated facilities and spacecraft. That such particles are created in solar flares is not a surprise, but this is the first time their immediate effects have been detected.

The results of this research have far-reaching implications for gaining valuable knowledge through remote detection of relativistic antiparticles at the Sun and, potentially, other astrophysical objects by means of radio-telescope observations. The ability to detect these antiparticles in an astrophysical source promises to enhance our understanding of the basic structure of matter and high-energy processes such as solar flares, which regularly have a widespread and disruptive terrestrial impact, but also offer a natural laboratory to address the most fundamental mysteries of the universe we live in.

Monday, 8 July 2013

The meteor that exploded over Chelyabinsk, Russia on February 15, 2013 was so powerful that it sent out ultra-low frequency soundwaves that traveled around the world at least twice, according to new research published in the journal Geophysical Research Letters.

The meteor was estimated to be 17 meters (56 feet) in diameter and it weighed about 10,000 metric tons. It entered Earth’s atmosphere and approached Russia traveling at speeds near 20 kilometers per second (45,000 miles per hour). The meteor eventually exploded 19 to 24 kilometers (12 to 15 miles) above Earth’s surface. The shockwave from the explosion shattered windows and damaged buildings in nearby cities.

New analyses of data collected by a global network of 20 infrasound sensors indicate that some ultra-low frequency soundwaves from the explosion circled around the globe at least twice. Infrasound refers to low frequency sound that is below 20 Hz (Hertz) or 20 cycles per second. While humans are incapable of hearing infrasound, these soundwaves travel long distances and some animals such as whales and elephants can use this type of sound for communication purposes.

Sunday, 7 July 2013

The Lovell Telescope at Jodrell Bank inspired the first proposals to search for radio signals from extraterrestrial civilizations. (Credit: Anthony Holloway, University of Manchester)

A network has been launched to promote academic research in the UK relating to the Search for ExtraTerrestrial Intelligence (SETI). The UK SETI Research Network (UKSRN) brings together academics from 11 institutions across the country.

UKSRN covers a broad spectrum of research topics, including potential methods for detecting signals, the linguistic challenge of deciphering messages, the probability of an extraterrestrial civilization interacting with Earth and the longevity of civilizations.

Dr Alan Penny, the coordinator of UKSRN said, "We hope that the existence of the network will excite interest from people in the UK astronomical community that have been thinking about SETI and encourage them to contribute their work.

Dr Tim O'Brien from The University of Manchester's Jodrell Bank Observatory will describe the capability of the UK's recently commissioned e-MERLIN array of seven radio telescopes for SETI projects and report on progress in initial test observations.

"The first proposal to search for radio signals from extraterrestrial civilisations was actually inspired by the construction of the Lovell Telescope at Jodrell Bank," said O'Brien. "We went on to take part in the SETI Institute's Project Phoenix from 1998 to 2003, searching for signals from about a thousand nearby stars. At that time the equipment required to sift through the data was expensive and unusual, but our modern telescopes are potentially capable of conducting these type of observations as a matter of course."

Saturday, 6 July 2013

AR1785 has a “beta-gamma-delta” magnetic field that harbors energy for powerful X-class solar flares. Another active region trailing behind it, AR1787, is only slightly less potent, with a magnetic field capable of M-class eruptions …

Friday, 5 July 2013

Artist's impression of the 64-meter Parkes radio telescope shown with a bright radio burst blazing briefly far from the Milky Way's disk (red swath at right). The Milky Way image is from a hydrogen-alpha full-sky map.

If you’ve been waiting for mysterious radio signals from space, tune in. An international team of astronomers has detected four powerful bursts that appear to come from billions of light-years away. At that distance, the radio pulses would each have put out in a few thousandths of a second the same amount of energy that the Sun would need 10,000 years to emit.

(So no, it’s not E.T.)

The bizarre signals came to light as part of the High Time Resolution Universe survey, a project using the 64-meter Parkes radio telescope in Australia to search the sky for radio blips and pulsars, the spinning-lighthouse-like stellar corpses left behind by some supernovae. Because the pulsars we detect lie in our own galaxy, astronomers mostly look near the Milky Way’s plane when hunting for these zombie stars. But when grad student Dan Thornton (University of Manchester, U.K., and CSIRO, Australia) started digging through normally “boring” data far from the galaxy’s dusty gleam, he stumbled across the four enigmatic bursts.

In this Monday, July 1, 2013 file photo, Bay Area Rapid Transit trains are parked at the station in Millbrae, Calif. Commuter rail service is resuming Friday, July 5, 2013 in the San Francisco Bay area after unions called off a strike, agreeing with the transit agency to extend a labor contract for a month while they continue bargaining.

Commuter rail service will resume Friday in the San Francisco Bay area after unions called off a strike, agreeing with the transit agency to extend a labor contract for a month while they continue bargaining.

The current contract between BART and the Service Employees International Union (SEIU), Local 1021 and the Amalgamated Transit Union (ATU), Local 1555, will be extended for 30 days after expiring earlier this week.

BART General Manager Grace Crunican said there is a wide gap of disagreements between the two sides.

"Unfortunately, the issues that brought us to this point remain unresolved," Crunican said. "Despite lots of hard work, BART and its unions have failed to come to an agreement on contract issues that matter to all of us today and into the future."